Injective Edge Chromatic Index of a Graph
نویسندگان
چکیده
Three edges e1, e2 and e3 in a graph G are consecutive if they form a path (in this order) or a cycle of length three. An injective edge coloring of a graph G = (V,E) is a coloring c of the edges of G such that if e1, e2 and e3 are consecutive edges in G, then c(e1) 6= c(e3). The injective edge coloring number χ ′ i(G) is the minimum number of colors permitted in such a coloring. In this paper, exact values of χ ′ i(G) for several classes of graphs are obtained, upper and lower bounds for χ ′ i(G) are introduced and it is proven that checking whether χ ′ i(G) = k is NP-complete. AMS Subject Classification 05C15
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